/Engine/Source/Runtime/Engine/Classes/Engine/DataTable.h
Copies RowData into table. That is: create Row if not found and copy data into the RowMap based on RowData. This is a "copy in" operation, so changing the passed in RowData after the fact does nothing.
virtual void AddRow ( [FName](API\Runtime\Core\UObject\FName) RowName, const [FTableRowBase](API\Runtime\Engine\Engine\FTableRowBase) & RowData )